External Operating Program Changeover - Viessmann Vitotronic 200 Installation And Service Instructions For Contractors

External functions
(cont.)
Function
One of the following functions:
External blocking
■
Mixer CLOSE
■
External changeover, stepped / modulating burner
External demand
Connections to EA1 extension
Function

External operating program changeover

External blocking
External demand
External operating program changeover
!
Please note
Live contacts lead to short circuits or phase fail-
ure.
The external connection must be potential-
free.
Function
Control unit Vitotronic control unit
Connection Plug
1
143
B
A
B
Contact
Closed The manually pre-selected operating program is changed over in line with the following
■
table "External operating program changeover".
Note
The changeover can be achieved separately for heating circuits 1 to 3.
Open The manually pre-selected operating program is active.
■
Parameter With parameter "08" in the "General"
group assign the function to the heating cir-
cuits.
External operating program changeover
.1/ .2
aVD aVD
A
2 3
Floating contact
To the control unit
Electrical connections
Plug
.2/ .3
aVD aVD
aVH .1/ aVH .2
.2/ .3
aVH aVH
Contact
DE1, DE2 or DE3
DE1, DE2 or DE3
DE1, DE2 or DE3
or
0 to 10 V input
EA1 extension
DE1, DE2 or DE3
B
DE1 DE3
DE2
A A A
Floating contact
A
EA1 extension
B
Set "42" (DE1), "43" (DE2) or "44" (DE3)
■
in the "General" group to 1.
In parameter "20" in the "Heating cir-
■
cuit..." group, the external operating pro-
gram changeover function can be as-
signed to the heating circuits.
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